This invention relates generally to sliding window assemblies for use in vehicles and, more particularly, to a window assembly having an improved mechanism for moving a window panel into a closed, sealed position over a window opening and a method for manufacturing a sliding window assembly.
Many utility vehicles, including vans and pickup trucks, have large fixed panels of glass. To improve circulation, the fixed window panels may contain sliding panels adapted to move and provide a window opening. One example of such a panel assembly appears with increasing frequency as the horizontally movable rear window of pickup trucks. Such sliding rear windows or backlights are often provided to the truck manufacturer, or in the after-market, as window frame assemblies. Current commercially available sliding window assemblies are mechanically complex having large numbers of components (30 to 40), resulting in increased cost. Moreover, despite the relative complexity, many commercially available sliding window assemblies do not seal well resulting in air and water leaking past the seals. For example, a typical commercially available sliding window panel assembly generally includes a welded aluminum frame which is sized to fit in the body panel opening. The inner face of the frame provides a continuous channel which supports the upper and lower edges of the sliding window pane. A pair of fixed window panes are supported in a second, inwardly opening channel adjacent the first. The edges of the fixed window panels are often supported by vertical struts which are secured between the upper and lower portions of the frame. The remaining sides of the fixed window panes are then secured or sealed in the frame. Often, a lip is provided on the struts or frame which is configured to engage the sliding window panels to prevent leakage of moisture when the windows are in the closed position. For example, see U.S. Pat. No. 4,124,054 to Spretnjak.
U.S. Pat. No. 4,561,224 to Jelens discloses a sliding window assembly having a continuous frame constructed of a thermoplastic material. When assembled, the sliding window assembly provides a unit frame configured to receive one or more fixed window panels and a sliding window. The peripheral edge of the stationary window panels receive a channel molding which, in turn, is positioned within and sealed within channels formed within the frame assembly. This particular construction retains the fixed window panel assemblies in a "three-sided" encapsulation. The frame assembly also includes an outwardly extending seal which is mounted along and around the perimeter of the window frame in an outwardly facing channel. The seal snugly fits within the body opening and is sealed and retained therein to seal the window assembly with the vehicle.
Other sliding window assemblies have been provided which utilize both metal and polymeric structures. One example of such a structure is shown in U.S. Pat. No. 5,228,740 to Saltzman. In general, the Saltzman window frame assembly uses a metallic frame having inwardly facing channels. An outwardly facing channel is also formed in the frame. One or more sliding window frames are disposed in the inwardly facing channels for movement between open and closed positions. Seals having opposed securing shoulders that cooperatively interact with a latch are provided to secure the seal in the second channel. A lip extending from the seal engages the sliding window frames. The fixed window panels are disposed in the second inwardly facing channel linearly adjacent the seal for closing a portion of the frame and overlapping the sliding window frames. A polymeric cover is secured with the front face of the frame and is secured within the outwardly facing channel of the frame. A lip portion extends outwardly from the cover to engage the body panel for centering the frame assembly relative to the opening in the body panel. The metallic frame and the elastomeric covering are adhered in the window opening by a bead of adhesive.
In U.S. Pat. No. 5,294,168 to Kronbetter, a variation of this structure is provided wherein the welded aluminum frame and elastomeric members are combined to provide a frame assembly adapted to fit within an opening of a body panel. The welded metal frame includes an outwardly facing channel formed in the outer periphery. The supporting member has a continuous lip portion which extends outwardly from the outwardly facing channel. The lip portion provides a protecting and centering function which acts circumjacent the outer periphery or perimeter of the metal frame. When the frame assembly is fitted into the opening of the body panel, the supporting lip prevents contact between the metal frame and the painted surface of the body panel.
U.S. Pat. No. 4,850,139 to Tiesler teaches a sliding window assembly for a vehicle which has a fixed window in a frame which is substantially flush with the frame at its exterior, and includes a sliding window movable between open and closed positions and releasable locks for locking the sliding window in its closed position. The sliding window, when moved to its open position, is parallel to and behind the fixed window. When moved forward to its closed position, the sliding window is automatically cammed and moved outwardly so as to lie in the same plane and flush with the fixed windows.
A further disadvantage associated with the prior sliding window assemblies is that few are capable of providing a true flush or single-sided window assembly. That is to say that the frame retaining the fixed and sliding window panels always has a portion which is exposed on the exterior side of the window panel. Currently available sliding window panel assemblies would not comport with the current trend for flush-mounted window panels. Moreover, many commercially available sliding window panel assemblies do not provide the desired sealing performance. Their relative mechanical complexity also makes them more expensive to produce.